/** * OpenAL cross platform audio library * Copyright (C) 2009 by Chris Robinson. * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. * Or go to http://www.gnu.org/copyleft/lgpl.html */ #include "config.h" #include #include #include "alMain.h" #include "alFilter.h" #include "alAuxEffectSlot.h" #include "alError.h" #include "alu.h" typedef struct ALmodulatorState { DERIVE_FROM_TYPE(ALeffectState); enum { SINUSOID, SAWTOOTH, SQUARE } Waveform; ALuint index; ALuint step; ALfloat Gain[MaxChannels]; FILTER iirFilter; ALfloat history[1]; } ALmodulatorState; #define WAVEFORM_FRACBITS 24 #define WAVEFORM_FRACONE (1<> (WAVEFORM_FRACBITS - 1)) & 1); } static __inline ALfloat hpFilter1P(FILTER *iir, ALuint offset, ALfloat input) { ALfloat *history = &iir->history[offset]; ALfloat a = iir->coeff; ALfloat output = input; output = output + (history[0]-output)*a; history[0] = output; return input - output; } #define DECL_TEMPLATE(func) \ static void Process##func(ALmodulatorState *state, ALuint SamplesToDo, \ const ALfloat *RESTRICT SamplesIn, \ ALfloat (*RESTRICT SamplesOut)[BUFFERSIZE]) \ { \ const ALuint step = state->step; \ ALuint index = state->index; \ ALuint base; \ \ for(base = 0;base < SamplesToDo;) \ { \ ALfloat temps[64]; \ ALuint td = minu(SamplesToDo-base, 64); \ ALuint i, k; \ \ for(i = 0;i < td;i++) \ { \ ALfloat samp; \ samp = SamplesIn[base+i]; \ samp = hpFilter1P(&state->iirFilter, 0, samp); \ \ index += step; \ index &= WAVEFORM_FRACMASK; \ temps[i] = samp * func(index); \ } \ \ for(k = 0;k < MaxChannels;k++) \ { \ ALfloat gain = state->Gain[k]; \ if(!(gain > 0.00001f)) \ continue; \ \ for(i = 0;i < td;i++) \ SamplesOut[k][base+i] += gain * temps[i]; \ } \ \ base += td; \ } \ state->index = index; \ } DECL_TEMPLATE(Sin) DECL_TEMPLATE(Saw) DECL_TEMPLATE(Square) #undef DECL_TEMPLATE static ALvoid ModulatorDestroy(ALeffectState *effect) { ALmodulatorState *state = GET_PARENT_TYPE(ALmodulatorState, ALeffectState, effect); free(state); } static ALboolean ModulatorDeviceUpdate(ALeffectState *effect, ALCdevice *Device) { return AL_TRUE; (void)effect; (void)Device; } static ALvoid ModulatorUpdate(ALeffectState *effect, ALCdevice *Device, const ALeffectslot *Slot) { ALmodulatorState *state = GET_PARENT_TYPE(ALmodulatorState, ALeffectState, effect); ALfloat gain, cw, a = 0.0f; ALuint index; if(Slot->effect.Modulator.Waveform == AL_RING_MODULATOR_SINUSOID) state->Waveform = SINUSOID; else if(Slot->effect.Modulator.Waveform == AL_RING_MODULATOR_SAWTOOTH) state->Waveform = SAWTOOTH; else if(Slot->effect.Modulator.Waveform == AL_RING_MODULATOR_SQUARE) state->Waveform = SQUARE; state->step = fastf2u(Slot->effect.Modulator.Frequency*WAVEFORM_FRACONE / Device->Frequency); if(state->step == 0) state->step = 1; cw = cosf(F_PI*2.0f * Slot->effect.Modulator.HighPassCutoff / Device->Frequency); a = (2.0f-cw) - sqrtf(powf(2.0f-cw, 2.0f) - 1.0f); state->iirFilter.coeff = a; gain = sqrtf(1.0f/Device->NumChan); gain *= Slot->Gain; for(index = 0;index < MaxChannels;index++) state->Gain[index] = 0.0f; for(index = 0;index < Device->NumChan;index++) { enum Channel chan = Device->Speaker2Chan[index]; state->Gain[chan] = gain; } } static ALvoid ModulatorProcess(ALeffectState *effect, ALuint SamplesToDo, const ALfloat *RESTRICT SamplesIn, ALfloat (*RESTRICT SamplesOut)[BUFFERSIZE]) { ALmodulatorState *state = GET_PARENT_TYPE(ALmodulatorState, ALeffectState, effect); switch(state->Waveform) { case SINUSOID: ProcessSin(state, SamplesToDo, SamplesIn, SamplesOut); break; case SAWTOOTH: ProcessSaw(state, SamplesToDo, SamplesIn, SamplesOut); break; case SQUARE: ProcessSquare(state, SamplesToDo, SamplesIn, SamplesOut); break; } } ALeffectState *ModulatorCreate(void) { ALmodulatorState *state; state = malloc(sizeof(*state)); if(!state) return NULL; GET_DERIVED_TYPE(ALeffectState, state)->Destroy = ModulatorDestroy; GET_DERIVED_TYPE(ALeffectState, state)->DeviceUpdate = ModulatorDeviceUpdate; GET_DERIVED_TYPE(ALeffectState, state)->Update = ModulatorUpdate; GET_DERIVED_TYPE(ALeffectState, state)->Process = ModulatorProcess; state->index = 0; state->step = 1; state->iirFilter.coeff = 0.0f; state->iirFilter.history[0] = 0.0f; return GET_DERIVED_TYPE(ALeffectState, state); } void mod_SetParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat val) { switch(param) { case AL_RING_MODULATOR_FREQUENCY: if(val >= AL_RING_MODULATOR_MIN_FREQUENCY && val <= AL_RING_MODULATOR_MAX_FREQUENCY) effect->Modulator.Frequency = val; else alSetError(context, AL_INVALID_VALUE); break; case AL_RING_MODULATOR_HIGHPASS_CUTOFF: if(val >= AL_RING_MODULATOR_MIN_HIGHPASS_CUTOFF && val <= AL_RING_MODULATOR_MAX_HIGHPASS_CUTOFF) effect->Modulator.HighPassCutoff = val; else alSetError(context, AL_INVALID_VALUE); break; default: alSetError(context, AL_INVALID_ENUM); break; } } void mod_SetParamfv(ALeffect *effect, ALCcontext *context, ALenum param, const ALfloat *vals) { mod_SetParamf(effect, context, param, vals[0]); } void mod_SetParami(ALeffect *effect, ALCcontext *context, ALenum param, ALint val) { switch(param) { case AL_RING_MODULATOR_FREQUENCY: case AL_RING_MODULATOR_HIGHPASS_CUTOFF: mod_SetParamf(effect, context, param, (ALfloat)val); break; case AL_RING_MODULATOR_WAVEFORM: if(val >= AL_RING_MODULATOR_MIN_WAVEFORM && val <= AL_RING_MODULATOR_MAX_WAVEFORM) effect->Modulator.Waveform = val; else alSetError(context, AL_INVALID_VALUE); break; default: alSetError(context, AL_INVALID_ENUM); break; } } void mod_SetParamiv(ALeffect *effect, ALCcontext *context, ALenum param, const ALint *vals) { mod_SetParami(effect, context, param, vals[0]); } void mod_GetParami(ALeffect *effect, ALCcontext *context, ALenum param, ALint *val) { switch(param) { case AL_RING_MODULATOR_FREQUENCY: *val = (ALint)effect->Modulator.Frequency; break; case AL_RING_MODULATOR_HIGHPASS_CUTOFF: *val = (ALint)effect->Modulator.HighPassCutoff; break; case AL_RING_MODULATOR_WAVEFORM: *val = effect->Modulator.Waveform; break; default: alSetError(context, AL_INVALID_ENUM); break; } } void mod_GetParamiv(ALeffect *effect, ALCcontext *context, ALenum param, ALint *vals) { mod_GetParami(effect, context, param, vals); } void mod_GetParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *val) { switch(param) { case AL_RING_MODULATOR_FREQUENCY: *val = effect->Modulator.Frequency; break; case AL_RING_MODULATOR_HIGHPASS_CUTOFF: *val = effect->Modulator.HighPassCutoff; break; default: alSetError(context, AL_INVALID_ENUM); break; } } void mod_GetParamfv(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *vals) { mod_GetParamf(effect, context, param, vals); }